1. BackType Connect / IntenseDebate – BackType incorporates Twitter mentions into your comment stream.

It unfortunately is not yet compatible with another favorite plugin of mine called IntenseDebate, which adds comment threading and other useful tools to the default comment functionality in WordPress. It can also synchronize with the basic WordPress system, so it is easy to turn on and off.

2. DB Cache + Hyper Cache – DB Cache speeds up database access by caching common queries. Hyper Cache makes static versions of Web pages (like WP Super Cache, but I’ve found it more focused and streamlined in its approach). The combination excels at reducing server resource consumption and serving the maximum number of visitors with the minimum resource use.

3. Tweetable – Automatically sends your new postings to Twitter, with the nice bonus of adding your blog name to each post. So, for example, my postings say “via in propria persona.” It also integrates Twitter into your WordPress dashboard, allowing you to easily Tweet from within WordPress.

4. WP Greetbox – Adds a message automatically to the top of your postings to encourage visitors to subscribe, Stumble, etc. Visitors from Digg get an encouragement to “Digg this,” those from StumbleUpon to “Stumble this,” etc.

5. Zemanta – While not perfect, this is a must-have plugin that makes it easy to add contextual information to your postings: pictures,  tags, and related links.

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